Device for bending metal strip



Oct. 6, 1959 c. w. BARNES DEVICE FOR BENDING METAL STRIP Filed March 21, 1958 uywzzvron CHARLES w. BARNES AT TQRNEYS United States Patent The present invention relates to a device for bending a workpiece and, more particularly, to apparatus for imparting reproducible bends and loops to elongated ductile stock such as a metal bar, rod, strip, slab, and the like.

In the art of metal working, it is often desired to bend a strip of wrought iron, for example, into an arcuate shape and more often into a loop for decorative or utilitarian purposes. At present such loops are formed in a metal strip by placing the strip between two fixed pegs which are spaced apart a given distance and then slowly bending the strip about one of the pegs. A certain amount of skill is required in order to obtain a smooth loop, since the strip must be simultaneously advanced in the direction of its length between the pegs as the loop is formed. Further, the same pegs are used by skilled artisans to bend loops of varying diameters. accommodate stock of different thicknesses, prior bending devices have required the bending pins to be reset and placed at different distances from each other in a fixed relationship.

In contrast, by means of my bending device an amateur can bend an elongated workpiece into loops of varying design without moving the workpiece in the direction of its length while the bend is being imparted. Further the present bending table is adapted to permit formation of curves or loops of varying radii and with reproducible and semi-precision results.

In one form of my invention, I use a bending table having a plurality of bending pegs or lugs of varying cross-sections or diameters. Instead of associating a companion peg with each bending peg and at a fixed distance therefrom, I use a cam operated type of holding means which is arranged with respect to each bending peg to afford a clamping or pinching action in cooperation with any of the bending pegs on a workpiece disposed between the holding means and a selected bend ing peg. The workpiece can then be bent around such selected peg to any degree desired, even exceeding 360, to acquire the general peripheral configuration of that peg.

It is, therefore, a principal object of the present invention to provide an improved bending device.

Another object is to provide a bending device by which reproducible results can be'obtained by an amateur.

A further object is to provide a bending device in which the feed stock need not be advanced in the direction of its length while a bend or loop is being imparted.

A still further object is to provide a bending device in which bending pins are not spaced from each other in fixed relation but provide a clamping or pinching action on a workpiece placed therebetween.

Other objects will become apparent as the description proceeds.

To the accomplishment of the foregoing and related ends, the invention consists of the features hereinafter fully described and particularly pointed out in the claims,

Also, to v ICC the annexed drawing and following disclosure describing in detail the invention, such drawing and disclosure illustrating however, but one or more of the various ways in which the invention may be practiced.

In said annexed drawing:

Figure 1. is a perspective view of a bending table embodying the present invention.

Figure 2 is a perspective view of a cam handle tha may be used with the table of Figure 1, and

Figure 3 is a plan view of the table and handle of Figures 1 and 2, respectively, when assembled and illustrating the manner in which a bend is imparted to a strip. 7 I

Referring to the drawing, the embodiment disclosed includes a work or bending table 10'which may be fixed to a suitable support by screws or bolts 11. A pivot "point or pin 12 projects upwardly from substantially the center of the table 10 and is enclosed by a surrounding ring of upstanding bending pegs or lugs 13. While the pegs 13 are illustrated in their prefer-red circular form or cross-section, it will be understood that these bending pegs may be elliptical, egg-shaped, polygonal, or

still otherwise shaped in cross-section, the purpose of the pegs'13 being substantially to impart their peripheral configuration to a workpiece bent thereabout as hereinafter described. Accordingly, the pegs 13 may if de-' 'Ihe pivot pin 12 cooperates with a cam handle 14 having at one end a cylindrical or shank portion 15. A hole 1 6 of a size freely to receive the pin 12 is eccentrically bored in the portion 15 as illustrated in Figure 2. When the handle 14 and table 10 are assembled, the handle thus eccentrically pivots about the pin 12, that is, about an axis substantially normal to the plane of the table 10 and moves toward the pins 13 to provide a camming action. It will be noted that preferably the handle may be pivoted either in a clockwise or counterclockwise direction as viewed in Figure 3 to afford this action with respect to any of the pegs 13.

As indicated in Figure 3, the bending pegs 13 are stationed sufiicient-ly close to the path described by the periphery of the shank portion 15 as it turns about pin 12 to clamp a workpiece between the shank portion 15 and a selected peg 13. In practice, the end of a strip 17 is placed adjacent one of the pegs 13. The handle 14 is then turned so as releasably to clinch or clamp the strip 17 against the selected peg. While the strip is thus held, it is bent around the selected peg for any given distance which may be for substantially 360 or more if desired.

It will now be apparent that I have provided an improved bending device. Loops and curves are easily imparted to a suitable workpiece by an amateur with my device and such loops and curves are moreover reproducible with semi-precision. Little or no skill is required and particularly the metal strip need not be continually fed between bending pegs in the direction of its length to effect a desired loop. It will also be noted that the shank portion 15 and a selected peg 13 cooperate to clamp a strip 17 in place rather than define a predetermined spaced gap therebetween. In thismanner, variations in thickness of the stock are automatically accounted for, and pegs need not be reset because of changes in feed stock.

Other forms embodying the features of the invention may be employed, change being made as regards the features herein disclosed, provided those stated by any of the following claims or the equivalent of such features be employed.

1 therefore particularly point out and distinctly claim as my invention: 7 v

1. A device for bending a workpiece including .a work table having a plurality ,of upstanding spaced-apart peg members, said members being of different thicknesses" to impart bends of corresponding shapes, and a clamp ,pivotallymounted on the .work table to pivot toward any selected upstanding member: and pinch said workpiece thereagainst to permit a bending of the workpiece thereabout.

2. Apparatus for bending an elongated workpiece including a work table having a cam member pivotally mounted with respect thereto, a plurality of lugs on the work table spaced from the cam member and from each other and varying in cross-sectional dimensions, each lug being sufiiciently adjacent said cam memberito provide apinching action on a workpiece-positioned between said lug and cam member upon pivoting of said member toward said lug to permit bending of the workpiece, about said lug. I p

3. Apparatus for imparting reproducible bends in a ductile elongated workpiece including a work table, ,a cam member mounted on the work table for pivoting about an axis substantially normal to the work table, a series of pegs spaced from the cam member and from each other, said pegs beingof selected different sizes and sufiiciently adjacent to the path described by pivoting the cam member about said axis to clamp the workpiece between said cam member and a selected peg, whereby the workpiece can be bent around the selected peg to a desired degree to acquire the general peripheral configuration of said peg.

4. Apparatus for imparting reproducible bends in a metal rod, bar, strip, slab, and the like articles including in combination: a work table :having a pivot pin, cam means adapted to receive the :pin and pivot thereabout, a plurality of generally circular and upstanding lugs on the work table spaced from each other and substantially ringing the pivot pin, said lugs being of difierent diameters, each lug being located sufiiciently'near the cam means to afford a releasable clamping action therewith on a metal article placed therebetween to permit the article to be bent around a selected lug.

5. Apparatus as defined in claim 4 wherein said cam member is a handle having adjacent one end an .eccentrically located bore to receive said pivot pin.

6. The apparatus of claim 3 whereinisaidicam member is detachably mounted on said work table.

ReferencesCited-in the file of this patent UNITED STATES PATENTS n. 181,423 Moulthrop Not/[12, 1957 1 ,042,112 ,Hartman Oct. .22, .1912 1,250,869 Kirby Dec. 18, .1917 2,212, tl5 ,Butler Aug. 2Q, .1940 

